The research included in this proposal will investigate the low- temperature theoretical behavior of several systems that display macroscopic quantum properties. Laughlin has recently suggested that particles obeying half fractional statistics would exhibit superconductivity. They will continue their study of this model for high-Tc superconductors, focusing on the excitation spectrum and the effect of a repulsive short-range potential, the screening of the long-range gauge forces, and the response to an external magnetic field, both at zero temperature and at finite temperature. The behavior of precessing dissipative domain walls in superfluid 3He-A will be investigated with the hydrodynamic model of orbital dynamics, with particular attention to the stability of these dynamic textures, the response to external magnetic fields, and the effect of dipole unlocking. The quasi- classical formalism will be used to extend their previous studies of superfluid 3He in severly confined geometries beyond the Ginzburg-Landau regime. They initially plan to analyze planar boundaries, but they eventually seek to treat flow through a constriction as a model for a weak link.
